


Burn the Midnight Oil

by EatYourSparkOut



Category: The Transformers (IDW Generation One), Transformers - All Media Types
Genre: Chair Sex, Edging, Friends With Benefits, Getting Back Together, Knotting, Like 4 Million Years Later, M/M, Past Relationship(s), Porn with Feelings, Riding, Size Difference, Size Kink, Sticky Sexual Interfacing, Strength Kink
Language: English
Status: Completed
Published: 2019-09-15
Updated: 2019-09-15
Packaged: 2020-10-17 14:54:53
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 7,763
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/20622887
Author URL: https://archiveofourown.org/users/EatYourSparkOut/pseuds/EatYourSparkOut
Summary: Ratchet rekindles a med school fling, for better or for worse.





	Burn the Midnight Oil

**Author's Note:**

> Hi, I'm here to say that Flatline not only fucks, he _fucks_.
> 
> This ship hit me like a freight train. All it took was seeing [this pic](https://twitter.com/arrahja/status/1166408079036076034?s=20) on twitter, and suddenly I was writing them an entire history. I have no excuses except that IDW gave us a really spicy medic and then didn't flesh him out, and what else was I supposed to do with that?
> 
> I usually try to stick to Cybertronian swears, but Ratchet says 'damn' a lot because I cannot possibly divorce him from Bones in my mind.
> 
> Oh, and Flatline has claws. I don't make the rules.

Ratchet had a problem. 

A big, complicated, and achingly _familiar_ problem. 

When Flatline had come aboard, asking for a lift to the nearest port, he'd anticipated some awkwardness—maybe a bit of tension. They hadn’t parted on the best terms, after all. 

Eons had passed since they’d gone their separate ways, but Ratchet could still recall with crystal clarity the events that’d led to their split. The same, tired, old argument—rehashed in cramped dorm rooms, and crowded dining halls. His growing annoyance with Flatline’s radical bent, and his drive to get involved with increasingly reactionary dissenters. Ratchet distinctly remembered calling him ‘a damn fool, who was going to get himself killed’, and Flatline storming off in a huff. He’d returned from lecture that day to find their shared room cleared of all of Flatline’s possessions—as though he’d never existed at all. Later, he’d learned that Flatline had withdrawn from the med program—left not just the school, but the city. 

Ratchet had been furious. He’d thought—He didn’t know what he’d thought. It’d just been a little fun, after all. They’d always been open—never exclusive, never serious. Roommates. Convenient. He’d distracted himself, found new friends—many of whom were just as eager to ‘face—and tried not to dwell on it.

Then he’d had gotten busy—with his new practice, and with the clinic in the Dead End. The revolution had ramped up, and he’d tried not to wonder whether Flatline was in the thick of it; whether his illicit hobby of patching up Kaonite gladiators and radicals had grown beyond sympathizing, and led him to join the ‘Cons.

Years later, some grainy footage on the other side of a battlefield—a glimpse of black and red amongst the wreckage, and an incriminating badge—and he hadn’t had to wonder anymore. 

And though the sting had faded—a half-healed wound from a distant lifetime—Ratchet had anticipated a bristly reunion. They hadn’t had time to acknowledge one another on Cybertron—working hard to patch everyone up in the wake of Shockwave’s failed power grab—but The Lost Light medbay was a much more confined, and tight-knit space; avoidance would be impossible. 

He’d been right, of course. The first few shifts were awkward, permeated by First Aid’s nervous chatter, and his own icy silence. 

What he _hadn’t_ anticipated was how quickly they’d find their feet—how short-lived that period of uneasy cohabitation would be. Flatline had ignored the barbed wire cage of his field, dodged his equally barbed tongue, and cracked the jokes that’d always made him groan back at the academy. He was still tactile—bumping Ratchet good-naturedly, and clapping large servos on his shoulder after a job well done. Ratchet could have told him to cut it out—rejected the familiarity—but he hadn’t. He’d found himself loosening, bit by bit. 

By the end of the first week, they’d hit their stride—slinging the same old banter, and working in tandem as though their ideological spat hadn’t torn their friendship wide open, and led to a stubborn, two-way radio silence for the better part of four million years.

Ratchet had forgotten how much he _liked_ Flatline. He was _enjoying_ having him on board. 

And he was mad about it.

He channeled that irritation as he yanked Whirl’s rotor back into place—a bit harder than necessary. 

“Ow!” Whirl complained, kicking the berth reflexively. “_Yeesh_, careful with the merchandise, Doc.”

“Maybe if you didn’t keep damaging the “merchandise” by attempting to re-enact “fruit ninja” with your blades, we wouldn’t be here for the third time this month.” The Lost Light being devoid of fruit, Whirl had been ordering mecha to throw other things at him—most of which did _not_ immediately pulverize upon contact with his rotors. With a long-weary sigh, Ratchet fished out a piece of glass that he’d missed. 

“Pfft, where’s the fun in that?”

“If you think he’s bad, you should try Vortex,” Flatline snorted, from where he was reorganizing the supply shelves. “One time I had to fish out a mech’s leg from between his rotors. Wouldn’t tell me how it’d gotten there, which in hindsight, was probably for the best.”

“Yeah? Big whoop. One time I was fragging this mech—guy had a rotary kink a mile wide, let me tell you—and it was kind of weird, but I was like ‘hey man, I’m not gonna judge how you get your rocks off’ so I told him he could stick his—”

“_And_ we’ve heard enough,” Ratchet interjected. 

“Eh. You had to be there,” Whirl said with a shrug. He narrowed his optic at Flatline. “And lucky for us both, _you_ won’t be touching me, Mr. Tall, Dark and Ugly. These rotors are a decepti-dick free zone.” 

Ratchet yanked the other bent rotor into alignment, more forcefully than the first.

“_Ow_. What’d I _say_?”

“No,” Ratchet growled. “_You’re_ lucky you’ve got two highly-trained and fully capable doctors to play sparkling-sitter. And between you and me, _he’s_ the nicer one,” he added, jerking his head in Flatline’s direction. 

Whirl’s optic cycled wider, but for once in his life he held his tongue. 

Ratchet got the feeling that the rest of the crew—whose reaction to Flatline had been lukewarm at best, antagonistic at worst—were surprised at how seamlessly he’d transitioned into his medbay. He got the feeling that the majority of that surprise came from how tolerant _he_ had been—the notorious Hatchet, rigid and uncompromising. They hadn’t expected to see him getting cozy with a ‘Con.

Oh, he’d made a stink at first, just on principle—taken his gripes to command, and his doubts. He had a reputation to maintain. But he wasn’t so mired in those principles, or his own, personal grudges, that he’d been prepared turn down a pair of capable servos—and regardless of their rocky past, there was no question that Flatline was a competent medic. He hadn’t _technically_ finished his formal training at the academy, but years of following the front lines had shaped him into a damn good trauma surgeon. 

Of course, the crew might have been less surprised, if they’d known that he and Flatline had been friends, once upon a time. Maybe more. Mostly, Ratchet avoided thinking about it too hard, because their ‘friendship’ had consisted largely of drinking and fragging—and frequent, late night conversations he didn't feel like analyzing, thank you very much—and if he thought about it too hard he might be tempted to fall back into that old routine. 

Which frankly, was a _terrible_ idea. 

His little moment of introspection had given Whirl the chance to bounce back from his surprise. He looked Flatline up and down, as though sizing him up—and Ratchet swore Whirl was the only bot he’d met that could pull off a convincing leer without a mouth.

“Yeah? How nice? Because if he wants to kiss it better I’ve got a few places he can start. Like my aft. Oh! And my spi—”

“_Alright_,” Ratchet interrupted again, not willing to let Whirl finish that sentence. Not least because it bordered on sexual harassment, but also because it called up a few choice memories, and he refused to humour the tingling heat they dredged up with them. “Get out of here. And if I see you here again before the week’s up, I’ll weld your aft to the berth and see if that keeps you in line.”

“Ooh, promise?” 

Ratchet shoved him off the medberth. 

“Get.”

Whirl blew a raspberry on his way out, which was really, the best he could have hoped for. 

“You don’t have to do that, you know,” Flatline said, low and amused. 

Ratchet’s hackles shot up. 

“Do what?” he demanded. So maybe he wasn’t a _hundred_ percent adjusted to Flatline’s presence yet.

“Defend my honour,” Flatline said. “I’m an ex-’Con on a ship full of Autobots; it’s not anything I wasn’t prepared for.”

“War’s over,” Ratchet grunted. He looked down at his datapad, and pretended to double-check Whirl’s file. 

“Hm. You and I both know that doesn’t matter.”

Ratchet didn’t like the reminder, but he supposed that it was something he’d have to get used to. His ongoing, and _spirited_ debates with Drift regarding the underlying principles of the Decepticon movement had tempered his views _somewhat_—to the point where he could understand, if not _agree_ with the choices mecha had made. In the end, they were all the products of their circumstances. 

But he wasn’t going to tell Flatline that, and it didn’t get him off the hook. 

Plus, Flatline had picked the ‘Cons, but unlike Drift, or Ambulon, he’d only renounced them _after_ the war had concluded. Ratchet didn’t know how to feel about that. He didn’t like it, mostly.

“Well, they’re gonna have to get used to it,” he said dismissively. Whatever his own feelings, it was important that the crew saw a united medbay. They needed to trust that their attendant’s faction had no bearing on the level of care they’d receive, or else it’d only be a downward spiral from there. “You’ve been onboard a month, and you’ve already seen how much traffic we get. Extra servos are extra servos, and mecha won’t care whose they are when they’re the thing keeping them from bleeding out from yet another self-inflicted gunshot wound.” Or the next time someone decided that they’d give laser tag with real lasers a go. 

“They _do_ seem to treat us like a revolving door,” Flatline observed, with that same undercurrent of amusement. 

Ratchet shorted. “You have no idea.” 

They worked in easy silence for a while—Flatline prepping the trays for tomorrow’s surgery, as Ratchet reviewed the files. And that was the problem wasn’t it? The thing that had him grinding his dentae in frustration. Flatline was _easy_—easy to talk to, easy to work with, easy to haul down into a berth and—

The stylus snapped under the sudden pressure of his fingers, and he growled under his breath. That was the second one this week. 

“Rough day?” 

Ratchet cast Flatline a sardonic look. 

“Aren’t they all?” 

He received a low, rumbling laugh in return, and the sound conjured up memories of an engine rumbling pleasantly against his armour, the sensation vibrating down to the protomesh and deeper, straight to his val—No. Nope. 

“I think you make them rougher than they need to be,” Flatline said.

“Yeah, well. I’m good at that.” 

“And bad at letting yourself relax. I remember.” 

Ratchet looked sidelong at him. Flatine was seemingly absorbed in his work, his frame broadcasting nothing but nonchalance. He didn’t _think_ that Flatline was implying anything, but it was hard to tell, considering their main method of ‘relaxation’ had always tended towards the physical. 

And therein lay the _other_ half of his problem. They’d fallen so easily into a routine that Ratchet was having a hard time not remembering how well they’d meshed in areas _outside_ of work and study—namely, the berth.

Flatline was big, and sturdy, with broad servos that were more than capable of supporting your weight on the off-chance you ended up hauled up and eaten out in some storage closet. He was all intense optics, and sharp edges, and Ratchet looked at his frankly indecent number of chest vents, and remembered how fun it’d been to shove his fingers into them, until Flatline’s vocoder crackled with excess charge. 

Flatline was still lamentably attractive, still very much Ratchet’s type, and right _there_.

“Hand me that wrench, would you?” he grunted, banishing that line of thought. 

It’d been ages since he’d had a good roll in the berth—courtesy of all the responsibilities and social complications that came with being CMO. He was wound tightly enough that even his frequent attempts to rub out out hadn’t done much good. But he wasn’t about to let his libido overrule his common sense. He wasn’t that oversexed med student anymore. 

Better to focus on the loose monitor that needed his attention.

Flatline passed the wrench his way. Their servos brushed as he handed it off, and Ratchet tried to ignore the static that danced up his spinal strut. 

He grunted a ‘thanks’ and bent down to fiddle with the monitor. He suspected that <strike>Whirl</strike> _someone_ had been tampering with them during their extended stays, just to get a rise out of him. So far, he hadn’t been able to catch them at it, but he was _this_ close to storming down to the security room and reviewing the tapes himself. 

“Here, let me help,” Flatline offered. He stepped forward to hold the screen in place, and it was infinitely easier with someone to steady it. 

“A_ha_” Ratchet said triumphantly, as the monitor stabilized. 

He straightened up, only to realize how close Flatline had gotten. The other medic clapped a servo on his shoulder, and the heat seeped through his armour to the tense cables underneath. 

Ratchet’s own temperature rose a few degrees. There he went again, with the touching. 

“And on that note,” Flatline said, “I think it’s time we called it a night.” 

Tempting. But then Ratchet looked around the medbay—taking stock of the myriad of things left to do. He thought about the stack of half-finished paperwork still sitting on his desk, and shook his head—shrugging off Flatline’s servo before his core temperature could rise high enough to kick his fans on. 

“There’s too much to do,” he said. 

“And we’ve already stayed two hours past the end of our shift,” Flatline pointed out. 

“Tch. We’re used to worse.”

Flatline glanced at him, expression unreadable. “The point is that we don’t _have_ to be— not anymore,” he said. “You can cut yourself some slack, you know.”

“No war doesn’t mean I’m gonna let my medbay slide into disrepair,” Ratchet said mulishly, crossing his arms. 

Flatline mirrored him, his gaze thick with disapproval. He stared down at Ratchet, and Ratchet stared defiantly back. 

But Flatline had never won any of their matches in the past, and after a few seconds he relented with a snort. 

“Remind me to send you some of the more recent studies on the detrimental effects of skipping recharge,” he said. 

“Noted.”

“I guess it _was_ too much to hope that you’d mellowed out in your old age.” 

“Remind me, which of us is older again?” 

Flatline waved him off. “A measly three hundred years doesn’t count.” 

“Mmhm.”

Flatline huffed, but it was a good-natured sound. He’d never been one to take Ratchet’s gruff personally. “Fine,” he said. “If you won’t take a nap, will you at least join me for a drink?” He inclined his head in the direction of their office. They were sharing, for the time being. “The place won’t fall to pieces if you kick back for an hour.”

He shouldn’t. But they were well into the night cycle, which meant that things were quieting down, and his shift was technically over, and First Aid was somewhere in the bay—prepared to handle any late night emergencies. 

“One drink,” Ratchet said, a little dubiously. He had dozens of memory files to remind him that they’d rarely stopped at one, but he supposed that like him, Flatline’s capacity to overindulge had dried up under the weight of his responsibilities. 

“One drink,” Flatline confirmed. 

Well, one drink couldn’t hurt. 

“Alright, you win. Lead the way.”

***

Two drinks in, Ratchet decided he was glad he’d taken him up on the offer. 

Flatline was sprawled in the comfortable office chair, his field loose and open. He’d offered the chair to Ratchet first, but he’d waved the suggestion away. Flatline was the bigger mech; he needed the room. 

Ratchet had pulled up one of the guest chairs to join him at the corner of the desk, and was now sipping leisurely at the cube of triple-filtered engex that Flatline had poured him. 

So far, they’d spent the majority of the time in relaxed silence, flipping through their respective datapads. Flatline looked up every so often to comment on something in the article that he was reading. He’d begun with medical journals, but at this point was well into trashy pop mags; Ratchet had already been subjected to one awful personality quiz.

“Want to find out what flavour of energon you are?”

“I cannot possibly emphasize to you how much I _don’t_ want that.”

Flatline nodded sagely. 

“Acidic”, he concluded.

Ratchet chucked his rust stick at him, rather than finish it, and Flatline ducked his head, chuckling. He tossed the datapad back onto the desk, and then propped his head on his fist to regard Ratchet with an inscrutable expression. 

“So,” Flatline drawled, with good humour. “What’s new with you?” He knew exactly how ridiculous—how loaded—that question was, and Ratchet crossed his arms as he leaned back. 

“Oh, you know,” he said. “Ex-warlord captaining the ship. At least three cases of rust rash—possibly more—because during the last pit stop, our _other_ illustrious captain stook his spike where it didn’t belong.” Namely, into an alien species known for carrying viruses that had little effect on _them_, but that didn’t exactly agree with Cybertronian systems. When Ratchet had delivered the prognosis, he’d gotten a cheery two thumbs-up and a bright ‘worth it’. “You?” he asked. 

Flatline’s mask had been down for a while, and his mouth—still weirdly compelling, and filled with sharp teeth—curved into a rueful smile.

“About the same. Yesterday, I found an effigy constructed from one of the EKGs hanging outside my habsuite, which led to a very fun meeting with Magnus.”

Ratchet tried to stifle his laugh, which led to a rather conspicuous reset of his vocalizer. 

“Can’t say you didn’t bring it on yourself,” he muttered, and Flatline groaned. 

“Oh no. We are _not_ going to blame my political choices every time I wake to find that someone has sharpied ‘decepti-creep’, or a cartoon depiction of a spike on my faceplate.”

“You’re right,” Ratchet agreed. “The second one’s a little on the nose, don’t you think?”

Flatline shot him an unimpressed look.

“I’m just saying; If you hadn’t been so bull-headed, and rushed off to join the _revolution_—” Ratchet stopped. Sighed. “No, you’re right, actually. I don’t want to talk about it. Let’s just drop it.” That was a three drink conversation, at the very least.

Flatline shrugged. 

“I’ve got no regrets,” he said simply. But then he paused, and looked at Ratchet. “Okay, maybe a few. We never got a real goodbye, after all.” 

“That an apology?”

“Do you want it to be?” 

Ratchet thought about it, swishing the last of his drink around the bottom of his cube. The years had healed the wound, left scar tissue where there’d once been a raw gash, and the anger he should’ve felt—had _expected_ to feel—just wasn’t there. 

“No,” he said finally. And he meant it. “I came to terms with everything a while ago.”

Flatline didn’t look like he quite believed him. Fair enough. 

“We were young,” Ratchet said slowly, “and hot-headed, and we made our choices.” A shrug. “I still don’t agree with yours—I think you were an _idiot_, really—but what’s done is done.” 

Flatline nodded thoughtfully, tapping at his cube with a claw. 

“You know,” he said wryly. “I think we just talked about it.” 

Ratchet growled. So they had. 

“And I’m sorry anyway,” he added. “You were an aft, but that didn’t mean I had to outdo you so _spectacularly_.”

‘Fine, whatever,” Ratchet said. “But if you wanna keep going down this path—or worse, debate ideology with me—you’re gonna need to get a few more drinks into me. _Then_ I’ll be happy to tell you in detail why you were, and continue to be, that idiot”. 

Ratchet took a sip from his cube, and found it empty. 

He reached for the bottle, only for Flatline to pull it out of his reach. 

“Really?”

“I promised you one drink,” Flatline chuckled. “And I didn’t stop you at two, but I’d rather spend this night talking to sober Ratchet. Drunk Ratchet might remember that he’s mad at me, and I have a lot of faith in your ability to effectively dispose of a body.”

“I’m not gonna slag you,” Ratchet said. “I need you in the Bay.” _Maybe frag you_ his processor offered, and if that wasn’t a sign that he should quit while he was ahead...

Flatine tossed him a crooked smile. “We do make a pretty good team.” 

“We do,” Ratchet agreed begrudgingly. 

Flatline slid the bottle back in range but Ratchet didn’t go for it. Flatline was right. Right now, he was pleasantly buzzed—enjoying the warm prickle under his armour, and the relaxed slant of his field. Any more, and he’d probably regret it in the morning. 

He pulled a sealed container of mid-grade from his subspace, and poured that in instead.

“And you do good work, for a med school dropout,” Ratchet added, just to needle him.

“We were graduating in _two months_.”

“Never took your boards though, did you?” 

Flatline pointed accusingly at him. “You know, none of the other medstaff are this mean to me. _First Aid_ appreciates me. I bet if I asked, he’d tell me that upholding my principles was _brave_. That I didn’t need certification from a bunch of outmoded mecha sitting on their dusty pedestals to be a good doctor.”

Ratchet rolled his optics, and ignored the jealousy that needled at him. It wasn’t his business who Flatline set his optics on. First Aid was cute. Flatline’s type.

“First Aid would tell you _all_ of that, huh? Maybe we should comm him, to be sure.”

“No need. I’ve got this.” 

Flatline cleared his vocalizer.

“Oh _Flatline_, you’re so brave for standing up to those _tyrants_,” he said, in the worst, most high-pitched rendition of First Aid that Ratchet had ever had the misfortune to hear. “And so _dashing_, too. I want to assist on _all_ of your surgeries.”

“You’re an idiot,” Ratchet told him flatly, but he was struggling to keep the corners of his mouth from twitching. “And considering that ‘Aid is due to take over from me, I think it’d be the other way around.”

Flatline shrugged. “Works for me. You know better than anyone that I don’t mind being bossed around.” One of his optics flickered in a quick wink. 

“How much of that have _you_ had again?” Ratchet asked—nodding at the bottle, and trying to ignore the jealousy that was working itself deeper into his spark. Stupid.

“You’ve been watching me,” Flatline pointed out, “and unlike some mecha, I’ve only had _one_.”

Ratchet narrowed his optics. 

“I missed this,” Flatline said suddenly, which wasn’t the usual response to being glared at by the notorious Autobot CMO.

“What, the joy of my company?” Ratchet asked sarcastically.

“Sure. Is that so hard to imagine?” 

It was, actually. 

“No one really wants to “hang out” with an old rust bucket like me,” Ratchet said, emphasizing the statement with air quotes. 

“First off, stop doing that with your fingers—because I can’t take you seriously,” Flatline said, as he almost snorted out his next sip of energon. “Second, if you’re a rust bucket, what does that make _me_?”

“I thought the three hundred years didn’t count?” Ratchet asked dryly. Besides, Flatline was still…. Well.

Ratchet knew the years and the stress hadn’t been kind to _him_—he was practically coming apart at the seams. Flatline, on the other servo, had fared better; he was still a mass of smooth black plating, and clean, strong lines, and smoldering red optics. Simply put, he was still a hot piece of aft. 

Flatline didn’t rise to the bait. “Don’t sell yourself short, Ratch,” he said simply. “You’re—what’s the word—ruggedly handsome.” 

Yeah, worn out. Got it. 

“Since when has flattery ever worked on me?” he asked, and Flatline shrugged. 

“It’s not flattery. It’s the truth. Besides, you’ve got plenty of other attractive qualities.”

“Yeah? Name them.” 

He felt like he was playing a very dangerous game, all of a sudden.

“Alright,” Flatline agreed easily. “You’re determined.”

“Stubborn.”

“Dedicated.”

“A workaholic.”

“Witty.”

“Abrasive.”

“Intelligent.”

Ratchet paused. 

“Yeah, alright. You can have that one.” 

“_Passionate_,” Flatline continued, and Ratchet proceeded to choke on his energon. 

He sputtered, coughing, and Flatline reached over to thump him on the back. It helped, a little, and soon he had himself under control. 

“You good?”

“Urgh. Yeah.”

“I mean it,” Flatline said. “You put your whole spark into everything that you do—you always have, even at cost to yourself. I don’t like what it does to you, but it’s admirable that you care so much.” His optics dimmed. “Not a lot of caring to go around these days.”

Ah, okay. So maybe he’d jumped to conclusions, by automatically assuming that Flatline had been talking about their, er—trysts. _He_ was being the licentious one here. 

Ratchet took another sip of his energon, and admired Flatline’s profile in the low light. 

His field went loose and weird, fluttering at the edges. Frag it. He didn’t need this.

Reigniting an old fling was just _asking_ for trouble. He knew that. They weren’t just two med students anymore—griping about exams, and shirking their studies to slink off to the new club that’d opened down the block. They had real duties now—things that were more important than their individual wants and needs. And they weren’t the same mecha they’d been back then. They were harder, more jaded—touched by time and war. There was no guarantee they’d still... fit. 

Ratchet was lonely, though. Tired. And Flatline seemed to have a knack for counteracting both of those things. He still pushed _all_ the right buttons.

Flatline caught him looking, and whatever he saw in Ratchet’s expression made his optics darken a shade.

“See something you like?” he asked. 

“I see a disaster waiting to happen.” 

“Why’s that?”

“We’ve changed. Both of us.”

Flatline was mellower for one—still set in his convictions, but more patient about it. 

“Not that much.”

Ratchet shook his head, not having expected to find himself in the deep end so quickly. He felt exposed—stripped down to his bare protoform. 

‘Why are you still here?” He asked, instead of refuting him. “Your port was three stops ago.” Flatline had given some lukewarm excuse at the time, and had continued to do so at each subsequent port. 

Flatline shrugged. 

“You haven’t given me a reason to leave.”

Ratchet’s self-restraint—having worn thinner and thinner as the night went on—finally snapped. 

“To Pit with it,” he muttered, returning his cube to the table with a decisive thunk. He stood up, and Flatline looked disappointed for a moment—and oddly resigned.

The look was short-lived, however, melting into a mild and pleased shock as Ratchet walked the few steps to his chair, and deposited himself unceremoniously into Flatline’s lap.

He met Flatline’s gaze in challenge, daring him to do something about it. 

Flatline’s fans kicked on with a hum. He didn’t seem inclined to remove him. The opposite, in fact. He wrapped a strong arm around Ratchet’s waist—planted a broad servo against the small of his back, and encouraged him to slide forward. Ratchet’s thighs—already draped across Flatline’s—spread wider, and he hooked his legs around the chair for support.

He wasn’t as limber as he’d used to be—and the cables in his groin protested at first—but he relaxed into the stretch, and bit by bit, he loosened up. The change in position brought their panels flush together, and his valve gave an interested throb—half-anticipation, half-memory. He rolled his hips, to relieve some of the ache behind his panel, and Flatline groaned. His field lashed out in unabashed lust, so Ratchet shuddered, and did it again. 

Flatline said his name hoarsely, and it snapped him back to reality.

“Are we really doing this?” he demanded, though he’d been the one to initiate. 

“Sure seems like it,” Flatline responded, and the servo on his back guided him, pressed him into another slow, firm grind. It barely scratched the itch; did more to stoke the fire in his belly than offer any real relief.

“That a good idea?” Ratchet asked roughly. He didn’t have a great track record with interpersonal relationships. They’d all crashed and burned, for some reason or another—and with their history, this was bound to be messy. But the low purr of Flatline’s engine, the heady pulse of his EM field—they presented a convincing counterargument. 

“It doesn’t have to mean anything,” Flatline offered, though his optics burned like coals.

“Flattering,” Ratchet said dryly, and turned his head away so as to not get trapped by the look. It was too intense—hinted at too many things that he wasn’t prepared to deal with.

Flatline huffed. “You know I didn’t mean it like that.” The servo that wasn’t at Ratchet’s back found its way to one of his shoulder-mounted tires, and proceeded to spin it lazily. The light touch generated more anticipation than it had any right to—stirred a hunger deep inside of him. 

“No, no. Please, tell me more about how you only want me for my frame,” he replied sarcastically. Another lazy spin sent a new cascade of charge crackling down the adjoining struts. He shifted, squeezing his thighs to try and relieve some of the ache behind his panels.

“I _meant_ it’s not like we haven't done this before. Casual.”

“Casual,” Ratchet repeated, and he wasn’t sure if he was agreeing with the assessment, or disputing it. He believed that’s what they’d convinced themselves of, at any rate. “That what _you_ want?” he asked. He’d brushed off the apology earlier; would Flatline do the same? He wasn’t sure he could handle anything else right now. 

He took to exploring Flatline’s headlights, bright and enticing as they were. He dragged his thumbs firmly along the inner edge—at the intersection of metal and glass—and whatever Flatline had been about to say died with a shudder. Ratchet licked at one of his thumbs, and did it again, and Flatline’s hips bumped up into his.

“N—you know what? How about we figure it out later,” Flatline suggested, in a strained tone of voice. 

“Still procrastinating, huh.” But yeah, later sounded good. Now wasn’t the time to put a name to something that’d always eluded definition. Right now, his main concern was the increasingly insistent throb of his array. 

“Well, you know. Bad habits,” Flatine said, and he revved his engine pointedly. 

Ratchet groaned, rolling his hips to chase the sensation. Heat bloomed under his chassis—in his spark, in his array. His valve pinged him helpfully, informing him that it was primed and ready to go, as though he could possibly miss the thick, syrupy heat pooling behind his panels. 

Flatline’s laughter reverberated through their joined armour, a teasing spectre of the power that lay under that chassis. 

“Again,” Ratchet demanded, and Flatline obliged.

He was prepared this time, but that didn’t do anything to dull the pleasure that ricocheted through his sensornet like a stray bullet, array to spark, and back to array again. It resonated in his field, bleeding back to Flatline’s where they overlapped, hot and heavy. Flatline squeezed his tire, and though it wasn’t particularly sensitive—he had to _drive_ on those—the reminder that Flatline was strong enough to leave depressions in the firm rubber set his fans to full blast.

Flatline’s fingers wormed their way into his wheel well, to stroke at the places that _were_ sensitive with surgical precision. He’d always liked playing with Ratchet’s wells, but the claws—the claws were new. He’d never been able to get so deep before. Arousal wound tight around his spark as they dug in, discovered seldom-touched nooks and crannies and dragged across sensitive protomesh. 

“You’re cheating,” Ratchet accused, through the static. Reformats hadn’t changed him so much that Flatline couldn’t guess at his weak points. Flatline’s frame, on the other servo, had gone through a more thorough overhaul. He was bulkier, thicker—rebuilt for war. 

“Not my fault that I studied, and you didn’t,” Flatline snickered. 

Ratchet retaliated by shoving his own blunt fingers into Flatline’s seams. He exploited their size difference to delve under the gaps in his armour—massaging the wires he found underneath, and pressing harder whenever Flatline twitched. Playing with the cables in his groin elicited a particularly vocal reaction, though the waist was a close second. He zeroed in on the chest vents he’d been eyeing earlier, exploring them _thoroughly_, and taking pride in the way that Flatline grunted, and pressed into his servos.

_Still got it_.

Ratchet’s valve cycled down on nothing, seeking something substantial to bear down on. His spike—knocking insistently against the back of his panel—was eager to be free of its confines. Evidence of his frame’s growing impatience showed in the fact that he was now very obviously _leaking_ through his seams—his thighs wet with arousal. 

He wasn’t the only one who’d noticed, either. 

“Want some help with that?” Flatline asked, darkly amused. 

“Think you’ve earned it?” Ratchet countered, but as fun as this was—letting the heat build and wind sluggishly through his lines, making Flatline wait—he was ready to move on to the main event.

“I think,” Flatline said, “that we’d both be happier if I was reacquainting myself with your ceiling node right about now.” 

Ratchet popped his panels, and the smell of ozone intensified. Flatline’s laughter segued into a sub-bass growl as Ratchet ground his bared valve against his armour, leaving smears of lubricant behind. His spike pressurized into a waiting servo, and he bucked with a muffled groan as Flatline dragged his servo up its length, root to tip in a firm stroke. 

Ratchet clutched at Flatline’s frame for support, and reached down to help. He curled his servo around Flatline’s and together they found a good rhythm—up and down and _twist_ until his thighs were trembling, and transfluid leaked from the tip. He was panting—_close_. 

Flatline’s servo slowed to a stop, and Ratchet was left teetering on the blissful knife-edge of overload. Sadistic bastard. 

“Hey,” Flatline purred. “You still like a stretch?” Ratchet’s engine stalled. 

_Frag, yes._

“Do it,” he growled. It came out shakier than he would have liked. 

“Sure you can handle it?” Flatline ribbed. “You get a lot of action, old mech?” He palmed the head of Ratchet’s spike, and Ratchet’s snappy retort turned into a muffled ‘Mmph’, as he jerked into the motion. 

And then Flatline released his spike—leaving it throbbing in protest—only to press a firm knuckle against his anterior node. Ratchet pushed into it with a groan, letting the pleasure wash over him. The pressure was mind-numbingly good, building and building with each minute twitch of his hips—

And once again, Flatline relented. His knuckle slipped away from Ratchet’s node, dragging down through his valve to gather the slick. He watched with heavy optics as Flatline’s tongue snaked out from his mouth to lick the finger clean. 

“Hm, a little thin. You getting enough iron in your diet? Flatline asked innocently. Ratchet slapped him on the chest. 

“Would you get on with it?” he demanded.

“Got somewhere to be?” Flatline punctuated the statement with another firm roll of his hips and this time the edge of his panel nudged against Ratchet’s node, and he saw stars. He chased the sensation, grinding down again—vents hitching as he caught the edge at a better angle. 

“I forgot what a spiketease you are,” he gasped.

“You make it too easy,” Flatline informed him, with a grin. And then he hauled Ratchet higher on his lap, angling his hips so that their panels—Ratchet’s valve, and his spike—were aligned. Flatline’s cover slid away with a small ‘snk’, and his core drew taut with anticipation. 

It’d been a while since they’d done this, but there were some things you never really forgot. 

Ratchet drew in a shuddering vent as Flatline pressurized—right into his valve. He was slow about it—more careful than than if they’d been doing this on a frequent basis—and that almost made it worse. It meant that Ratchet felt every micrometre of the spike’s progression, as it cleaved through his first ring of calipers, and lit up every node along the way.

Flatline hadn’t gotten any smaller—and it was definitely a _stretch_—but Ratchet was wet enough that the sting was minimal, and more than worth the feeling of _fullness_ that accompanied it. Flatline was watching him, all heat and dark optics, but Ratchet was too busy trying not to overload to put on a show. He curled fingers around the upper edge of Flatline’s chest armour to ground himself, and could only hold on as the thick spike continued to spread his twitching mesh—bearing down on his nodes with intense pressure. 

Ratchet was panting by the end of it, staring unseeingly into a point on Flatline’s shoulder as the spike finally came to a rest against his ceiling node. 

“You’ve got new mods,” he accused him weakly. He didn’t remember the other mech’s spike being so riddled with bumps and ridges before. In particular, the little nobs at the base were new—rubbing incessantly at the ring of sensors at the rim of his valve, and making his internals tighten with need,

“Don’t tell me you’re _complaining_” Flatline murmured. 

“I mean, a little _warning_ would have been nice,” Ratchet bit out, but Flatline shifted and the new angle pulled an indecent moan from him. His valve rippled weakly. 

It’d been a long time. Ratchet had forgotten how _good_ it felt to be stuffed to the brim like this. Flatline was hitting all of the deepset nodes he couldn’t reach with his fingers, and a toy didn’t _throb_ the same way, or conduct the same charge.

“Good?” Flatline asked, but he sounded as ruined as Ratchet felt, and he took gratification in knowing that he wasn’t the only one affected. 

“You know damn well it is,” he muttered hoarsely.

He squeezed his calipers deliberately, and Flatline made a strangled noise, bucking up as he pulled Ratchet down onto his spike. The motion ground the head of Flatline’s spike against his ceiling node, and Ratchet lost the battle to stave off his overload. It jolted through his frame—an unstoppable tide of wet heat that suffused him from spike to spark. Transfluid splattered across Flatline’s front, and gushed from his valve, adding to the mess he’d already made of their thighs. 

Ratchet shuddered as the aftershocks began to ebb, but rather than stop, he began grinding down, and the pleasure looped around—his charge building once again towards the inevitable. Flatline helped; he slid his servos under Ratchet’s thighs, using his strength to lift, and then ease him back down in a tortuous slide. Ratchet groaned as Flatline did it again—this time wrapping an arm firmly around his back, and pushing up with his own hips as he brought him down. 

Ratchet considered himself a pretty average-sized mech. He was no pretty, thin satellite—to be swept off his feet and carried over the doorstep. He was stocky. Practical. Flatline’s ability to manipulate him as though he weighed nothing spun his crankshaft like nothing else. A few choice memories swam to the front of his processor. Flatline picking him up to frag him quick and dirty in a supply closet. All the times he’d hoisted Ratchet up onto his shoulders to eat him out, or swallow down his spike. 

_Frag_. 

They found a good, rolling rhythm, and the office became a chorus of sharp gasps and low groans, interspersed by muffled curses. The lubricant ran, wet and messy between them. The simple eroticism of Flatline’s servos on his frame—supporting him, pulling his thighs wider so as to deepen their angle, and graze his nodes _just right_—ignited a new fire under Ratchet’s chassis. 

He was determined to ride Flatline into this chair until he couldn’t remember his own designation.

“You’re gonna kill me,” Flatline groaned, when Ratchet told him as much. 

“Out of practice?” he drawled, as though he weren’t halfway to another overload himself. 

“No, I’m pretty sure it’s just you.” The jagged heat that ripped through him at the admission was unexpected, and he faltered for a brief moment. “Besides, last time I checked, only _one_ of us had overloaded,” Flatline added breathlessly. 

Oh, was that a _challenge_? 

Ratchet sought to rectify that discrepancy. He focused on working the spike in his valve, squeezing down rhythmically, and rocking into his lap, and it didn’t take long for Flatline to sing his praises—a litany of ‘yes’, ‘harder’ and ‘like _that_’ erupting from his vocalizer. The heat spiralled higher, their fans climbing to a roar. 

“I’ve got another mod,” Flatline managed to groan.

“Y-yeah?” 

“Mmm, I think you might like it.” 

Flatline pinged him the specs, and Ratchet somehow scrounged up the processor power to open the file. Immediately, his mouth went dry. A thrill raced up his backstrut. 

“Yes?”

“Yes. _Pit_ yes”

Flatline didn’t make him wait for it. On the next grind, the base of his spike began to swell, and the stretch—already delicious—became that much more intense. Ratchet’s fingers scrabbled for purchase as his spike continued to expand, and Flatline’s servo caught his—interlacing their fingers and squeezing tight. Flatine pushed up once more, as the knot swelled and locked them together. 

Oh, that was _good_.

“That’s it,” Flatine growled, and the low timbre of his voice evoked a weak spasm from Ratchet’s valve. They were joined so tightly that movement was next to impossible, but Flatine’s spike prodded at his ceiling node, and another small grind was enough to make them groan in unison. 

“Servo. Give it here,” Ratchet managed, and used his hold on Flatline’s servo to tug it towards him. It was simple to take one of Flatline’s fingers into his mouth—to suckle it as though it were a hot, heavy spike laying against the flat of his tongue—and Flatline’s field _spiked_ with lust. 

“You are so slagging _hot_” he intoned. 

And when Flatline thrust up again, and the knot refused to budge—_tugging_ on oversensitized mesh—the pleasure crested sharply, and Ratchet came with a muffled shout. Untouched, like a bot fresh off the assembly line. His spike painted another line of transfluid across Flatline’s armour, and his weakly twitching calipers did their valiant best to drag him deeper, milking him for all that he was worth. 

Flatline’s spike pulsed _hard_ as he followed Ratchet over the edge. The charge crackled between their plating, coursing through his open sensornet and dragging him straight into another spiral of pleasure before the first had even faded from his circuits. Distantly, he heard Flatline groaning his name, but he was too busy weathering the unexpected storm of his second overload—sharp and raw, but so very _good_. 

Flatline’s finger slipped from his mouth, and Ratchet offlined his optics as the last waves of pleasure shuddered their way through his frame. He collapsed, shivering, against the sturdy weight of Flatline’s frame as his valve gushed more lubricant, and Flatline’s hips stuttered a few more times before slowing to a halt. 

They sagged into the chair, steam rising from their armour. 

It took a good minute to collect his thoughts, but when his processor and gyros had finally stopped spinning, Ratchet began to chuckle. They… this was not how he’d expected his night to go. 

One thing was for certain; he was going to be sore in the morning.

“I guess I was right,” Flatline observed breathlessly. “Things _haven’t_ changed all that much.”

“Oh, _shut_ it.” The order was rendered less effective by his unsteady delivery. 

Flatline licked his chevron in retaliation, and Ratchet twitched. The rough rasp of a tongue against such sensitive metal was _almost_ enough to make his spike stir in renewed interest, but he was tired, damn it. He swatted at him weakly. 

“Cut that out,” he groused.

Ratchet couldn’t be bothered to move. In all honesty, he didn’t know that he’d be able to if he tried. That third overload had rendered him all but immobile, and his struts felt… wiggly. 

“We should get to a berth,” Flatline pointed out. 

“Feel free,” Ratchet mumbled. “I’m not moving.” He knew he’d regret it later, when their combined mess had dried tacky between them, but right now he was too tired to care. “Too old for this,” he added, but there was no conviction in it, just satiated exhaustion. 

Flatline snorted. “You didn’t seem to think so a few minutes ago.” 

“Yeah, well. That’s your fault,” Ratchet grumbled. “Now, shut up; I’m trying to sleep.”

Flatline’s field took on a tiredly amused cant, and though his mod had yet to release them, he managed to rearrange them to a slightly more comfortable position. The rim of Ratchet’s valve had begun to ache, but it wasn’t unbearable; it’d be a pleasant reminder in the morning. He allowed himself to sink into the warm blanket of Flatline’s field, recharge creeping in at the edges of his processor. 

After a few moments, Flatline broke the silence again. 

“I was thinking I might stay on a little longer,” he said.

Ratchet grunted an acknowledgement. Flatline could do what he liked; he wasn’t about to kick him off the ship, if that’s what he was worried about.

“I was thinking that there might be mecha here who need me more.” 

“Your call,” Ratchet mumbled.There was no denying it, he liked having Flatline around. And he could certainly get used to _this_.

“Oh, and you don’t need to worry about First Aid,” Flatline added, and even with his optics off, Ratchet could practically see the smug bastard’s smirk. “I think I like being at the tender mercy of the current CMO.”

Ratchet’s spark did a weird little flip at that. He elected to ignore it.

“Good. Glad we’ve settled that,” he muttered. “Now, stop talking before I disable your vocoder, and you have to spend the next shift miming.”

Flatline pulled him close with a small chuckle.

As Ratchet drifted offline, he mustered enough awareness to realize that Flatline had tricked him into a nap after all. 

Damn it. He’d pay for that.

Later. 

For now, recharge sounded pretty good.

**Author's Note:**

> Ratchet likes big bots and he cannot lie. 
> 
> They're too old to sneak around like newly forgeds, but the Lost Light's storage closets see a little more action going forward. 
> 
> If you enjoyed this rarepair, drop me a line! I'm currently considering all the potential of a Drift/Ratchet/Flatline sandwich...
> 
> Also, [playlist](https://open.spotify.com/playlist/1EJZGf9PiKlMEEZ6ae71Gs?si=mQ6iRO6uSaWZCZcqBN2Hvg).


End file.
